1 EFET EWIV European Fusion Engineering and Technology Balance of Plant Requirements and Concepts for Tokamak Reactors Edgar Bogusch EFET / Framatome ANP GmbH 9 th Course on „Technology of Fusion Tokamak Reactors“ Erice, 26 July to 1 August 2004

2 EFET EWIV European Fusion Engineering and Technology Contents  Introduction  General Layout of Balance of Plant  Requirements of BoP for Tokamak Reactors  Conceptual BoP Layout for a Tokamak Reactor  Reactor Models of PPCS  Conclusions

3 EFET EWIV European Fusion Engineering and Technology Introduction A Power Plant can be divided into:  The Steam Supply System (thermal heat source)  Balance of Plant Systems (BoP) (systems for power conversion and distribution)

4 EFET EWIV European Fusion Engineering and Technology BoP Objectives  Efficient conversion of thermal power to electricity  Reliable electricity supply for its own components  Minimum contribution to the overall plant costs  High availability of systems and components  Reliable and effective operation of auxiliary systems

5 EFET EWIV European Fusion Engineering and Technology References  Designs of existing conventional and fission power plants  SEAFP Studies  Power Plant Conceptual Study (PPCS)

6 EFET EWIV European Fusion Engineering and Technology Objectives of the PPCS The Study has to demonstrate:  The credibility of the power plant design(s)  The claims for the safety and environmental advantages and for the economic viability of fusion power  The robustness of the analyses and conclusions  also relevant for the BoP Systems

7 EFET EWIV European Fusion Engineering and Technology Conventional Plants  Boiler  Heat transfer and conversion system incl. auxiliary systems

8 EFET EWIV European Fusion Engineering and Technology Schematic of a Combined Cycle Multi-Shaft Power Plant

9 EFET EWIV European Fusion Engineering and Technology Fission Power Plants Nuclear Fission Plants  Nuclear Steam Supply System (NSSS) (fission core, water/He/LM coolant)  Heat transfer and conversion system incl. auxiliary systems

10 EFET EWIV European Fusion Engineering and Technology EPR Layout

11 EFET EWIV European Fusion Engineering and Technology Fusion Power Plants Nuclear Fusion Plants (Tokamak-Type)  Tokamak core (fusion plasma)  Confinement systems  Plasma Heating systems  Primary cooling system (water, helium, Pb - 17Li coolants)  Heat transfer and conversion system incl. auxiliary systems

12 EFET EWIV European Fusion Engineering and Technology Important Systems and Components of the NSSS  Reactor/tokamak core  Reactor/vacuum vessel with all internals  Primary loop (pumps, intermediate heat exchangers)  DHR system  Primary auxiliary systems  Primary leak collection and leak detection systems  Fire fighting systems for Primary Systems  Core element handling  Component handling  Reactor protection system  Reactor-specific instrumentation and control systems

13 EFET EWIV European Fusion Engineering and Technology Important Systems and Components of the BoP  Buildings  Steam and power conversion system  Cooling water systems  Auxiliary systems (e.g. auxiliary steam, hot water/cold water, demineralized water, compressed air)  Ventilation systems  Fire fighting systems for conventional fires  Chemical water treatment  Elevators and hoists  Locks and gates  Treatment of radioactive waste  Plant and building drainage  Systems for the electrical auxiliary power supply  Non reactor-specific instrumentation and control systems

14 EFET EWIV European Fusion Engineering and Technology Strategy for a Fusion Power Plant To find a niche in the existing world of electricity producing power plants it is necessary to have:  Competitive construction and electricity production costs  Comparable availability The BoP systems have to provide a contribution to these requirements!

15 EFET EWIV European Fusion Engineering and Technology Requirements for Fusion Power Plants  Base-load electricity production  Steady-state operation  Load-following capabilities  Electrical power output equivalent to present LWR  Easy maintenance  Low recirculating power fraction

16 EFET EWIV European Fusion Engineering and Technology List of typical BoP Systems for a Tokamak Fusion Power Plant  Secondary Heat Transport System  Turbine Generator System  Cooling Water Auxiliary Systems  Water Treatment Plant  Compressed Air System  Fire Protection System  Electric Power System  HVAC System  Vacuum Vessel Pressure Suppression System  Other Auxiliary and Anxilary Systems

17 EFET EWIV European Fusion Engineering and Technology Heat Sources  Present Power Plants: Single heat source (boiler, fission core)  Fusion Power Plants Blanket and first wall Divertor Low temperature shield

18 EFET EWIV European Fusion Engineering and Technology BoP Systems with Specific Characteristics Relevant to a Tokamak Fusion Power Plant  Primary Heat Transfer System  Electric Power System  HVAC System  Vacuum Vessel Pressure Suppression System

19 EFET EWIV European Fusion Engineering and Technology Requirements for the BoP  Low contribution to the construction costs (standard components, minimum number of safety relevant systems)  High reliability and availability  Scheduled downtimes to be included in the tokamak scheduled downtimes

20 EFET EWIV European Fusion Engineering and Technology Topics for Scheduled Maintenance Frequency depends on:  Systems architecture (existence and number of redundancies)  Lifetime of most significant equipment or components Maintenance duration mainly depends on:  Scheduling of activities  Design of most significant equipment  Accessibility

21 EFET EWIV European Fusion Engineering and Technology Topics for Unscheduled Maintenance Frequency depend on:  Systems architecture (existence and number of redundancies)  Components reliability  Human factor (training, procedures) Unscheduled maintenance duration mainly depends on:  Design and accessibility of the less reliable components  Testability  Spare parts policy

22 EFET EWIV European Fusion Engineering and Technology PPCS Targets  Plant availability > 80%  Unscheduled availability < 7%  Two years full power operation  Four months shutdown

23 EFET EWIV European Fusion Engineering and Technology Availability and Reliability Notes 1. Estimated figures. Availability: here only the planned maintenance is accounted for. 2.The reliability accounts for non planned outages. It has been taken smaller for the more complicated systems. The quoted figures are indicative and open to interpretation; however, if they should change by  3% the basic results would not be significantly impacted. 3.The serviciability is the product of (1) x (2). 4.The process efficiency is the thermomechanical efficiency for thermal plants and the hydraulic efficiency for hydro plants.

24 EFET EWIV European Fusion Engineering and Technology Comparison of PPCS Reactor Models Model AModel BModel CModel D Breeder Material Pb – 17 LiLi 4 Si 0 4 Pb – 17 Li CoolantWaterHelium Pb – 17 Li Thermal (Fusion) Power (MW th ) 5,0003,6003,4002,500 Electric Power Output (MWe) 1,500 Efficiency (%) Recirculating Power Fraction

25 EFET EWIV European Fusion Engineering and Technology Power Conversion System Model A Primary heat in Primary heat out

26 EFET EWIV European Fusion Engineering and Technology Power Conversion System Model B

27 EFET EWIV European Fusion Engineering and Technology Heat Transfer System Model C Compressor 1Compressor 2Compressor 3 Heat Rejection HX Turbine Intercooler 1Intercooler 2Recuperator Generator ~

28 EFET EWIV European Fusion Engineering and Technology Heat Transfer System Model D

29 EFET EWIV European Fusion Engineering and Technology Example of Hydrogen/electricity Production Scheme ELECTRICITY Generator Steam Turbine Heat Exchanger Steam Generator TOKAMAK REACTOR He Coolant Divertor Coolant Circuit PbLi Pump Blanket Coolant Circuit COGENERATION (STEAM/WATER)

30 EFET EWIV European Fusion Engineering and Technology Similar PPCS technologies to Generation IV Fission Reactors  Gas Cooled Fast Reactor system - relevant synergies with Model B He coolant, He loops and Turbomachinery technologies (490ºC-850ºC He temperature ranges)  Very high - Temperature Reactor - relevant synergies with Model B and Model C High temperature, He loops and heat exchangers (1000ºC) for thermochemical H 2 production.  Supercritical - Water Cooled Reactor - Model A Model A may be further optimised for high pressure water cooled blankets and divertor operating above thermodynamic critical point of water (374ºC, 22.1 MPa).  Lead Cooled Fast Reactor - Model C Material technology, heat transport, energy conversion and chemistry for lead (PbLi/PbBi) coolant systems.

31 EFET EWIV European Fusion Engineering and Technology Conclusions  BoP systems play an important role for the reliable operation of a Fusion Power Plant.  Heat transfer system and power supply have to meet specific characteristics of fusion power.  The availability of the BoP has to compensate for the comparable low availability of the tokamak due to specific maintenance requirements.  High efficient plant designs have been described in the PPCS but require future technologies still to be developed.

32 EFET EWIV European Fusion Engineering and Technology Conclusions cont.  The availability factor is considered a key parameter in the Fusion Power Plant feasibility demonstration.  Experience in Fission Plants shows that BoP availability is an important contribution to this parameter.

33 EFET EWIV European Fusion Engineering and Technology The Future Source: FzK

34 EFET EWIV European Fusion Engineering and Technology Acknowledgements I would like thank my colleagues of EFDA, Framatome ANP and Siemens Power Generation for their input to this presentation, and in particular Felix Alonso of IBERTEF/Empresarios Agrupados for his valuable comments and support.

35 EFET EWIV European Fusion Engineering and Technology Any questions? Please go ahead!